Modular bill handling systems can process, check, store and dispense currency items such as bills. These systems can include a main module (e.g., a validating unit) and a spine chassis in which storage units can be attached. Bills accepted and processed by the bill handling system may be stored in the storage units. Periodically, servicemen may remove the storage module to a cash-room in order to empty the module of bills. In some cases, it may be necessary to ensure the security of the storage module so that the bills cannot be accessed improperly or without authorization.
The following disclosure relates to a type of storage module, for example, a lockable and removable cassette, that stores bills in a modular bill handling system.